I cant recall much about it. But it was animated and i thought it was treasure planet for a long time until i rewatched it. I only remember one scene where the group of heros had to sneak into a black tie affair of some sort in order to steal/obtain some information or object. Well when they get to the door there is a weapons check and everyone else had just one or two weapons, one guy in a full length trench coat had the whole thing full and proceeded to start unloading them all onto the table. Meanwhile everyone else is inside obtaining the info. Well just as he places the last weapon on the table and starts into the part everyone else comes running out in a hurry grabbing their weapons yelling they have to go now. So the guy grabs his stuff and they run to their ship just as people come running out after them they take off. Thats all i remember,but its killing me i cant remember the name of the movie.

I watched a movie when i was about 5 so it would have to be made before 1991. The beginning starts with a party at a huge mansion. The son of the family throwing the party is going around popping balloons behind people to scare them. When he comes to his best friend she turns just as he is popping the balloon which pops in her face and a piece gets stuck in her throat and she ends up choking to death. So the kid ends up going crazy after the funeral and kills his whole family and house staff. At the end he invites his teacher to dinner and as they sit down to eat she asks where his family is. He tells her her really appreciates everything she taught him but she forgot one thing. When she asks what he tells her “how to kill” and then proceeds to kill her and the movie ends.
I’ve been trying to figure out what it’s called for years.